Body zones
- Coronary Sinus: Main Vein of the Heart's Blood Flow
- Endocardium: Inner layer of the heart chamber walls
- Left Atrium: Upper Heart Chamber Receiving Blood
- left ventricle:heart's main pumping chamber
- Mitral Valve: Heart's Left Atrioventricular Valve
- heart muscle: the thick middle layer of the heart
- Pericardium: Protective Sac Surrounding the Heart
- Right Atrium: Upper Chamber of the Heart
- Right Ventricle: Lower heart chamber for blood flow
- Sinoatrial Node: Heart's Natural Pacemaker
- Hormonal System: Body's Chemical Messenger Network
- Hormones: Chemical Messengers in the Body
- Adrenocorticotropic Hormone: Stimulates Cortisol Production
- Adrenaline: A Hormone That Triggers Fight or Flight
- Aldosterone: Hormone Regulating Salt and Water Balance
- Androstenedione: A Hormone Involved in Hormonal Balance
- Calcitonin: Hormone Regulating Calcium Levels in Blood
- Cortisol: Stress Hormone and Its Effects on the Body
- DHEA: A Hormone Involved in Growth and Development
- Human Growth Hormone: Essential for Growth and Metabolism